1. Field of the Invention
The present invention relates to an ejector cycle device including an ejector for drawing refrigerant and a plurality of evaporators. The ejector cycle device can be effectively used for, for example, an air conditioner or a freezing device for freezing or/and refrigeration.
2. Description of the Related Art
A known ejector cycle device of this type is disclosed in JP Patent No. 3322263 (corresponding to U.S. Pat. Nos. 6,477,857, and 6,574,987). In this ejector cycle device, a first evaporator is arranged between a vapor/liquid separator and a downstream side in a flow of refrigerant of an ejector acting as the pressure of refrigerant and means for circulating refrigerant, and a second evaporator is arranged between the outlet of liquid refrigerant of the vapor/liquid separator and the suction port of refrigerant of the ejector.
According to this ejector cycle device, vapor-phase refrigerant discharged from the second evaporator is drawn into the ejector by the use of a pressure drop caused by a high-velocity flow of refrigerant at the time of expansion, and the velocity energy of refrigerant in expansion is converted to pressure energy in a diffuser part (pressure increasing part) so as to increase the pressure of refrigerant to be drawn into the compressor. Hence, the driving power of a compressor can be reduced.
These two evaporators can exert the action of absorbing heat (cooling action) in separate spaces or in the same space. Further, the JP Patent No. 3322263 describes that these two evaporators may cool a room.
However, in this ejector cycle device, the mass flow rate (hereinafter, mass flow rate is simply referred to as “flow rate”) of refrigerant branched to the second evaporator depends on the refrigerant drawing function of the ejector and hence the flow rate of refrigerant branched to the second evaporator cannot be independently adjusted.